Prepare for open-sourcing (#619)

* Add issue templates

* Update readme and docs for contributors

* Tune up the README.md

* Tune language a bit

* Tune copy

.github/ISSUE_TEMPLATE/feature_request.md

@@ -0,0 +1,24 @@
+---
+name: Feature request
+about: Suggest an idea for this project
+title: ''
+labels: feature-request
+assignees: ''
+
+---
+
+**Is your feature request related to a problem? Please describe.**
+
+<!-- A clear and concise description of what the problem is. Ex. I'm always frustrated when [...] -->
+
+**Describe the solution you'd like**
+
+<!-- A clear and concise description of what you want to happen. -->
+
+**Describe alternatives you've considered**
+
+<!-- A clear and concise description of any alternative solutions or features you've considered. -->
+
+**Additional context**
+
+<!-- Add any other context or screenshots about the feature request here. -->